Circuit controlling device



Nov. 7, 1944. w KUHN CIRCUIT CONTROLLING DEVICE Filed Jan. 29, 1934 2 Sheets-Sheet l Nov. 7, 1944.

lllll i C. W. KUHN CIRCUIT CONTROLLING DEVICE Filed Jan. 29, 1934 2 Sheets-Sheet 2 z I J 1 34 121 14 Patented Nov. 7, 1944 CIRCUIT CONTROLLING DEVICE Clarence W. Kuhn, Milwaukee, Wis., assignor to Cutler-Hammer, Inc., Milwaukee, Wis., a corporation of Delaware Application January 29, 1934, Serial No. 708,804

25 Claims.

This invention relates to circuit controlling devices and is particularly applicable to devices for controlling electric translating apparatus such as motor driven domestic refrigerators.

The invention has among its objects to provide a compact, efllcient and rugged control device ior motor driven apparatus such as electric refrigerators.

Another object is to provide a control device for apparatus of the aforesaid character including an improved manually operated switch of the free tripping overload type, or in other words, a switch which is automatically opened under overload conditions even though its manual operating means is deliberately held in circuit closing position.

Another object is to provide a switch of the aforesaid character which operates with a snap action when actuated either manually or automatically.

I Another object is to provide a free tripping overload switch which is adapted to be reset by movement of its manual control means in a direction to effect closure of the switch.

Another object is to provide a switch of the aforesaid character which is closable only upon resetting of its associated overload responsive mechanism.

Another object isto provide a free tripping overload switch of the aforesaid character having improved fluid condition responsive means associated therewith for effecting cyclic operation thereof. I

Another object is to provide an improved rei'rigerator control device consisting of a relatively small number of parts which can be readily manuiactured and assembled to provide a compact, emcient and durable control unit.

Various other objects and advantages of the invention will hereinafter appear.

The accompanying drawings illustrate an embodiment of the invention which will now be described, it being understood that various modifications may be made in the embodiment illustrated without departing from the spirit and scope of the appended claims.

In the drawings,

Figure l is a side elevatio-nal view of a control device embodying the invention, a cover associated with an enclosing casing for the device being removed.

Fig. 2 is a vertical sectional view of the device shown in Fig. 1.

substantially on line 3-3 of Fig. 1.

Figs. 4, 5, 6 and 7 are enlarged detail sectional views of the switch unit shown in Fig. 1.

Fig. 8 is a sectional view taken substantially on line 88 of Fig. 4.

Fig. 9 is a sectional view on line 99 of Fig. 8.

Fig. 10 is a sectional view taken substantially on line Ill-40 of Fig. 'I, and

Fig. 11 is an exploded perspective view of certain of the parts of the switch unit shown in Fig. 1.

The control device illustrated in Figs. 1 and 2 includes an insulating box-shaped enclosing casing I having a switch unit 2, and a fluid condition responsive device 3 mounted therein, said casing being provided with a removable side wall 4 shown in Fig. 3. As hereinafter set forth, the switch unit 2 is adapted to be controlled by the fluid condition responsive device 3 to effect starting and stopping of an electric refrigerator, and device 3 is shop adjusted to provide predetermined normal cycles of operation of the refrigerator and is also adjustable by rotation of aknob 5 mounted upon the front wall of casing i to provide for modification of such cycles. Also as hereinafter set forth, the switch unit 2 has an overload responsive mechanism associated therewith which is responsive to effect stopping of the refrigerator under predetermined overload conditions in the power circuit thereof, and said unit is provided with an operating knob 6 mounted upon the front wall of casing l, which is movable axially to start and stop the refrigerator at will, and to also effect resetting of the overload mechanism upon response thereof.

The switch unit 2 is provided with an insulating base 1 and the same includes a pair of stationary contacts 8 and 9 arranged upon opposite sides of said base as shown in Fig. 3 and a cooperating bridging contact to. Bridging contact I0 is provided with a snap operating mechanism which is carried by a bracket ll fixed to insulating base I. As shown in Fig. 8 said operating mechanism includes a pair of oppositely arranged U-shaped levers l2 and I3 pivotally mounted upon bracket H, and a tension spring l4 connected between the free ends of said levers and arranged between the side arms thereof. Bridging contact I0 is loosely mounted upon the lower end of lever l2 and is insulated therefrom, and lever I3 is operatively connected to knob 6.

-More specifically, insulating base 1 is secured to the. side wall I5 of casing I by a screw l6 and said base is recessed as shown in Fig. 3 on the Side adjacent said wall to receive bracket II and the parts carried thereby. Bracket II is con-' tructed as shown in Fig. 11, the same being provided with a horizontally arranged body portion II having depending side projections I3 and I3 and a depending front projection 20. Bracket II is secured to the insulating base I by screws 2I and 22 which extend through said base into tapped openings in the side projections I3 and I9. As shown in Figs. 4 and 8 the upper ends of the arms of lever I2 are provided with bearing portions 23 which seat within notches in the underside of the body portion I! of bracket II, while the lower ends of the arms of lever I3 are provided with bearing portions 24 which seat within notches in the upper side of the body portion of said bracket directly above the bearing portions 23.

Bridging contact I is loosely mounted upon a pin 28 secured to the lower end of lever I2 and is guided by an insulating block 21 interposed between the same and said lever. As shown in Fig. 9, the rear face of block 21 is recessed to receive bridging contact I0 and the front face of said block is recessed to receive lever I2 and is also provided with a center projection 23 which extends into an opening in said lever. Also as shown in Fig. 9, block 21 is provided with a center opening for receiving pin 26 and one end of said pin is riveted over a metal washer 23 which is insulated from lever I2 by an insulating washer so while the other end of said pin is provided with an enlarged head 3| which fits loosely within an opening in bridging contact I0 and engages block 21 to hold the same in place upon lever I2.

Lever I3 is operatively connected to knob 3 through the medum of a slider 32 mounted upon bracket II. Slider 32 is provided with a vertically arranged side arm 33 (Fig. 11) and the upper end of said arm is provided with a right angle extension 34 having a slot 35 therein for receiving lever I3, while the' lower end of said arm is provided with a hook projection 33 which is guided within a slot 31 in the side projection II of bracket II. The side arm 33 of slider 32 is also provided with a forwardly extending projection 38 which is guided within an opening 39 in the depending front projection 20 of bracket II. Projection 33 is bent with respect to the side arm 33 to provide a shoulder portion 40 (Fig-11) and the same has an opening 4I therein for receiving a connecting member 42 which is secured to the inner end of knob B by a rivet 43.

In connection with the foregoing it will be noted that slider 32 is movable by knob 6 to effect movement of lever I3 in opposite directions between the positions illustrated in Figs. 4 and 5. With lever I3 in the position shown in Fig. the axis of spring I4 is located to the right of the pivot of lever I2 and said latter lever is therefore biased to hold bridging contact II) in engagement with its cooperating stationary contacts 3 and 9. Upon outward movement of knob 6 lever I3 moves the spring I4 into a position wherein the axis thereof is located to the left of the pivot of lever I2. As soon as spring I4 assumes a position wherein the axis thereof is located slightly to the left of the pivot of lever I2 said lever moves with a snap action into the position shown in Fig. 4 to disengage bridging contact I0 from its cooperating stationary contacts 8 and 3. Upon inward movement of knob 3 bridging contact I0 moves with a snap action into the closed position shown in Fig. 5 when spring I3 assumes a position wherein the axis aseaao'r thereof is located slightly to the right of the pivot of lever I2.

The above described switch mechanism is provided with an overload responsive mechanism including an electro-thermal device 43 and a cooperating latch 43. Electro-thermal device 45 includes an electric heater 41 of helical form. arranged within a recess 43 in insulating base I, a tubular member 43 fixed within an opening in said base and having one end surrounded by said heater and a ratchet pin III located within said tubular member. Heater 41 is connected between contact 8 and a rearwardly extending terminal member 3| fixed to insulating base I and as shown in Fig. 10 one end of ratchet pin 33 is connected to the tubular member 43 by a solder connection 52, while the opposite end thereof is provided with an enlarged toothed head 33 to be engaged by the latch 48.

Latch 43 cooperates with the upper side of the toothed head 53 on ratchet pin 30, and as shown in Fig. 10 the under side of said latch rides upon aligned bearing parts 54 and 55, the former hearing part being formed on insulating base 1 and the latter comprising a pin secured to the side projection I3 of bracket II. Latch 43 is biased to move forwardly and also downwardly by a spring 56 having one end connected to said latch and its opposite end connected to the lower end of projection 20 on bracket II. The under side of latch 46 is provided with struckout portions forming a tooth 51 for engaging head 53 of the ratchet pin and a stop 53 for engaging bearing part 55. and the front end of said latch is provided with a projection 59 for engaging the spring I4. Said latch is also provided with a forwardly extending projection 30 arranged to cooperate with the shoulder portion 40 on slider 32 and the rear end thereof is provided with a surface 3| arranged to cooperate with a downwardly extending cam projection 62 on the rear end of the body portion I! of bracket II.

The operation of the aforedescribed overload responsive mechanism will now be described.

Latch 46 is normally held in the position shown in Fig. 5 against the action of spring 56 by engagement of its tooth 51 with the toothed head 53 of ratchet pin 50. With latch 46 in the position shown in Fig. 5 its projection 59 is located out of the path of movement of spring I4 and its projection B0 is located above the shoulder 40 on slider 32. The switch can thus be opened and closed as hereinbefore described without disturbing said latch.

As will be understood, when the switch is in closed position heater 4! is connected in the power circuit of the apparatus controlled by the switch and upon given overload conditions said heater effects fusing of the solder connection 52 to permit rotation of ratchet pin within the tubular member 49. Latch 46 is thus released to move forwardly under the action of spring 56 into a position shown in Fig. 7 wherein stop 53 engages bearing part 54. During movement of said latch into the position shown in Fig. 7 the projection 59 thereon engages spring I4 and bends the same so that the axis thereof assumes a position to the left of the pivots of levers I2 and I3. Lever I2 then operates with a snap action to move its associated bridging contact III into open position, and as is apparent the latch 46 will cause said lever to operate even though push button 6 is held in on position. On the other hand, if push button 6 is released lever I3 operates under the action of spring I4 to move said aaoaaor push button and the slider 32 outwardly into of! position.

It will be noted in connection with Fig. 7 that when latch 46 is released spring 53 is located to the left of bearing parts 54 and 55 and the front end of said latch is thus biased downwardly to provide for engagement of projection with the upper edge of the shoulder portion on slider 32. However, upon movement of knob 5 .and slider 32 into oil. position the shoulder portion 40 moves out of engagement with latch 48. The front end of latch 46 then moves downwardly under the action of spring 56 into engagement with a stop 63 on the side arm 33 of slider 32, and as shown in Fig. 6 the front end of the projection 60 on said latch is then positioned to engage with the rear face of the shoulder portion 40 on said slider.

As will now be set forth, latch 48 is reset and the switch is reclosed by movement of knob 6 inwardly into on position. As is apparent from Fig. 6. upon inward movement of slider 32 by knob 6 the shoulder portion 40 on said.slider engages the front end of projection 60 on latch 46 to slide said latch inwardly over the bearing parts 54 and 55. During inward movement of said latch from the position shown in Fig. 6, the surface 6! thereon engages the cam projection 62 on bracket Ii to tilt said latch upon the bearing parts 54 and 55 into a position wherein the front end of projection disengages the shoulder portion 40 on slider 32. Latch 46 is disengaged from slider 32 before spring H is moved into a position to effect closure of the switch and upon disengagement of said latch from said slider spring 56 is'located to the rear of bearing parts 54 and 55 and acts to move the tooth 51 of said latch into engagement with the toothed head 53. The latch is thus reset in the position shown in Fig. 5 and during final movement of knob 6 into on position lever i2 and the contact lil'carried thereby moves into circuit closing position with a snap action. In connection with the foregoing it should be noted that unless the electro-therrnal device 46 is in condition to retain the latch 46 in the position shown in Fig. 5 when the same is disengaged from slider 32, said latch will immediately return to the position shown in Fig. 7 to prevent reclosure of the switch by knob 6. It should also be noted that if the switch is opened manually or auto matically a portion of the knob 6 which is normally concealed within the opening in the front wall of casing i will be exposed to indicate that the switch is in open position.

To facilitate connection of the aforedescribed switch unit in the power circuit of the refrigerator, stationary contact 9 and terminal member 5i are provided with rearwardly extending portions which project through openings in the rear wall of casing in, as shown in Fig. 3, and are provided with terminal portions 9 and 5| arranged upon the rear face of said casing. Said terminal portions are enclosed by a terminal box having a conductor opening in the upper side thereof, and as shown in Fig. 2 said terminal box is secured to casing l by screw 86 which threads into a bushing 61 secured within therear wall of easing I.

As hereinbefore stated, the above described switch unit is adapted to be controlled by a fluid condition responsive device 3. As shown in Figs. 1 and 2 said device includes a bellows 10 secured adjacent the upper end of the rear wall of casing I and having a communicating pipe extension II on the rear end thereof. The pipe 1| Fill may be connected to the low pressure side of the refrigerator to provide for operation of the bellows by pressure in that part of the apparatus or it may contain an expansible gas and be arranged at a point contiguous to the refrigerating apparatus where the temperature and consequently the pressure within the pipe and bellows varies in accordance with operations of the refrigerator. The front end of bellows HI bears against a vertically arranged pivoted lever 12 having an adjustable spring I3 associated therewith which opposes expansive movements of the bellows, and said lever has a snap operating mechanism associated therewith for effecting operation of bridging contact I 0.

More specifically, lever 12 is carried by a bracket 14 havinga vertical leg 15 provided with an opening for receiving the front end of bellows 10 and a horizontal leg 16 arranged below said bellows. The upper end of leg 15 is arranged within a recess formed in the top wall of easing i and the rear end of leg 16 is provided with a projection 11 which is secured to casing I by a screw 18. Lever 12 has its upper end mounted upon a pin 19 carried by bracket 14 and the lower end of said lever is provided with a projection which extends rearwardly below the leg 18 of bracket 14. The spring 13 associated with lever 12 is held under compression between said lever and a nut 8| mounted upon a threaded stem 82 which is fixed to knob 5 by a screw 82. Nut 8! is recessed to receive a horizontally arranged rib 83 on wall i5 of casing I, said rib being shown in dotted lines in Fig. 2 and the stem 8! is rotatably mounted within an opening in the'front wall of easing i and is held against forward movement by a shoulder portion at thereon which engages the rear face of said wall. Thus upon rotation of knob 5 nut Bi moves axially upon the threaded stem 82 to vary the degree of compression of spring 13. As shown in Fig. 2, the inner face of knob 5 is provided with a channel for receiving a projection 85 on the front wall of casing l and a stop 86 Within said channel cooperates with saidprojection to limit rotation of said knob in opposite directions.

The snap operating mechanism associated with lever 12 includes a vertically arranged lever 81 and an over center sprin 88. Lever 81 has its upper end pivoted upon a pin 89 carried by the leg 16 of bracket 14 and said lever is provided with a. rearwardly extending projection 90 adjacent the lower end thereof. Spring 88 is held under compression between cup washers 9| and 82 and the former cup washer rides upon a pointed projection 93 fixed to extension 39 of lever 81 while the latter cup washer rides upon a pointed projection 94 fixed to projection 80 of lever 12. The lower end of lever 81 is movable in opposite d rections between the rear face of insulating base 1 of the snap operating mechanism and a threaded stop 95 carried by the bushing 6! and is arranged to operate the bridging contact i0 through the medium of a slidable insulating bar 96. The bar 96 is slidably mounted within a recess in base I and the rear end thereof is arranged to be engaged by lever 81 whilethe front end thereof is arranged to engage bridging contact in.

With lever 12 in the position shown in Fig. 1 spring 88 is positioned so that the force thereof acts on a line located in front of-pivot pin 89 of lever 81 and said spring thus acts to hold lever 81 in engagement with its associated stop 3!. Bridging contact I0 is thus adapted to be held in closed position as shown in Fig. 1 under ing circuit for the refrigerator driving motor.

With the driving motor in operation the temperature within the refrigerator decreases and upon a predetermined temperature drop determined by the degree of compression of spring 13 bellows l permits lever 12 to move rearwardly under the action of said spring towards the position shown in Fig. 2. During such inward movement of lever 12 spring ll assumes a position wherein the force thereof acts on a line located to the rear of the pivot pin I9 and said spring then acts to move lever 81 with a snap action from the position shown in Fig. 1 into the position shown in Fig. 2. Upon movement of lever 81 into the position shown in Fig. 2 bar 8| is moved forwardly to effect snap disengagement of bridging contact l0 from stationary contacts 8 and 8 for stopping of the refrigerator. The temperature within the refrigerator then increases and upon a predetermined temperature increase bellows 10 moves forwardly against the action of spring 13 into a position wherein spring 88 is positioned so that the force thereof acts on a line located in front of the pivot pin 89. Spring 88 then returns lever 81 with a snap action into the position shown in Fig. 1 and bridging contact l0 reengages its cooperating stationary contacts 8 and 8 under the action of spring II to effect restarting of the refrigerator.

As hereinbefore stated, the temperature at which the refrigerator is started and stopped is determined by the degree of compression of spring 13. In practice the nut 8| is shop adjusted with knob i in a given angular position to provide for starting and stopping of the refrigerator at predetermined temperature values to effect what may be termed normal cycles of operation of the refrigerator. Upon rotation of knob out of said predetermined angular position the degree of compression of spring 13 is changed to vary the temperature values at which the refrigerator is started and stopped or to effect what may be termed non-normal cycles of operation of the refrigerator. The stop 85 is also shop adjusted, and as is apparent such ad- Justment provides for variation of the point at which bridging contact in is opened during movement of lever 12' inwardly from the position shown in Fig. 1 to thereby eflect variation of the range of temperature drop required to eifect stopping of the refrigerator.

What I claim as new and desire to secure by Letters Patent is:

1. In a circuit controlling device, in combination, a movable switch element, manual operating means therefor including an overcenter spring for moving said element into and out of closed position with a snap action and for biasing said element to said position when operated thereto, a pressure responsive device for moving said element out of closed position against the action of said spring and an overload device responsive to move said element of out closed position through the medium of said spring, said overload device being resettable by said manual operating means.

switch element out of closed position, one of said devices being responsive to predetermined pressure conditions and the other being responsive to predetermined overload conditions, said latter device being responsive free from interference by said operating member and being resettable by said operating member upon movement of the latter in a direction to move said switch element into closed position.

3. In a circuit controlling device, in combination, a movable switch member pivoted about a fixed axis, a, manual operating member therefor, an overcenter spring permanently connecting said members and providing for snap movements of said switch member between open and closed positions upon movement of said operating member in opposite directions, a pressure device responsive to move said switch member out of closed position against the action of said overcenter spring and to permit reclosure thereof under the action of said sprin and an overload device responsive to move said spring with respect to said operating member and said switch member to provide for snap movement of said switch member into open position independently of said operating member, said overload device being resettable by said operating member.

4. In a circuit controlling device, in combination, a movable switch member, manual operating means therefor including a spring operating connection for moving said switch member into and out of closed position and for biasing said member to said position when operated thereto, a device responsive to predetermined conditions to move said switch member out of closed position against the action of said spring operating connection and to permit return thereof to closed position under the action of said spring operating connection, and an overload device responsive to move said switch member out of closed position through the medium of said spring operating connection, said overload device being resettable by said manual operating means.

5. In a circuit controlling device, in combination, a movable switch element pivoted about a fixed axis, manual operating means therefor including a spring for moving said element into and out of circuit closing position, saidelement when moved into such position being yieldingly held therein by said spring, a temperature responsive device for moving said element out of circuit closing position against the action of said spring and an overload device responsive to move said element out of circuit closing position through the medium of said spring, said overload device being re-settable by said manual operating means.

6. In a circuit controlling device, in combination, a movable switch element having biasing means associated therewith to yieldingly hold the same in closed position, a lever movable about a fixed axis between opposite extreme positions and arranged to open said switch element against the action of said biasing means during final movement into one of said extreme positions, and to permit reclosure of said switch element during initial movement out of said latter extreme position, an over-center spring for moving said lever in opposite directions between said extreme positions with a snap, and a fluid condition responsive device acting directly upon said spring to effect snap operation of said lever.

7. In an adjustable control device, in combination, amovable switch element having biasing means associated therewith for yieldingly holding the same in closed position, a pivoted lever movable in opposite directions between givan limits and arranged to open said switch element against the actionoi said biasing means during final movement into one 01 said limits and to permit reclosure of said switch element during initial movement out of said latter limit, an overcenter spring for moving said lever in opposite directions between said limitsv with a snap, a pressure responsive element acting directly upon said spring to eii'ect snap operation of said lever, spring means acting in opposition to said pressure responsive element, a range adjusting element for varying the tension of said spring M means and a differential adjusting element associated with said lever for varying one of the limits thereof.

8. In a controller for electric refrigerators, in

combination, a substantially rectangular box-like enclosing casing, a circuit controlling device mounted within said casing and having thermal overload means associated therewith for effecting circuit opening operation thereof, an. operating lever pivotally mounted within said casing and having an over-center spring associated therewith for moving the same in opposite directions between given extreme positions with a snap, said lever being arranged to open said circuit controlling device during final movement into one of said extreme positions and to effect closure of said device during initial movement out of said latter extreme position, a second lever pivotally mounted within said casing and arranged to operate said former lever through the medium of said over-center spring, a pressure operated bellows engaging said latter lever and secured to a wall on one side of said casing, a. spring arranged between said latter lever and a wall on the opposite side of said casing, and manual control means mounted on said last mentioned wall for varying the tension of said spring,

' for effecting resetting of said overload means upon'response thereof, and for effecting opening and reclosure of said circuit controlling device at will.

9. In a controller for electric refrigerators, in combination, a substantially rectangular box-like enclosing casing, a circuit controlling device mounted within said casing and having thermal overload means associated therewith for eifecting circuit opening operation thereof, a snap operating mechanism for said device including a pivoted lever movable in opposite directions between given extreme positions to open and close said device, a pressure operated bellows engaging said lever and mounted upon a wall on one side of said casing, a, spring for opposing movement of said lever by said bellows, said spring being arranged between said lever and a wall on the opposite side of said casing, and manual control means carried by said latter wall for varying the tension of said spring, for effecting resetting of said overload means upon response thereof and for effecting opening and reclosure of said circuit controlling device at will.

10. In a controller for electric refrigerators, in combination, a substantially rectangular boxlike enclosing casing, a circuit controlling device mounted within said casing and having thermal overload means associated therewith for efiecting circuit opening operation thereof, a supporting bracket fixed within said casing, a lever pivotally mounted upon said bracket and having an overcenter spring connected therewith for moving the same in opposite directions between given extreme positions with a snap, said lever being arranged to open said circuit controlling device during final movement thereof into one of said extrem positions and to eflect closure of said device during initial movement out of said latter extreme position, a second lever pivotally mount= ed upon said bracket and operatlvely connected to said former lever through the medium of said spring, a pressure operating bellows mounted upon said enclosing casing and engaging said lat ter lever on said side thereof, a spring engaging the opposite side of said lever to oppose operation thereof by said bellows and manual adjusting means mounted on one of the side walls of said enclosing casing for varying the tension of said spring, for effecting resetting of said thermal overload means upon response thereof, and for eflectin opening and reclosure of said circuit controlling device at will.

11. In a. circuit controlling device, in combine. tion, a, pivoted switch member, a manual operat ing member therefor, an over-center spring permanently connecting said members and providing for snap movement of said switch member be tween circuit opening and circuit closing posi-- tions upon movement of said operating member between opposite extreme positions, and an electro-thermally controlled device of the solder type having a spring biased part releasable automati cally under given electrical conditions to move said spring with respect to said members to provide. for snap movement of said switch member out of circuit closing position free from interference by said manual operating member and to also provide for movement of said manual operating member into circuit opening position upon release thereof, said spring biased part when released being engageable by said operating member to efiect resetting thereof upon movement of said operating member in a direction spring biased latch member normally held in a given position and releasable upon overload to move said circuit controlling member out of circult closing position independently of said operamng member and to also return said operating member to open circuit position upon release thereof, said latch member when released being resettable in normal position by said operating member upon a given movement of the latter out of open circuit'position, and said latch member when reset in normal position being disconnected from said operating member.

13. In a. circuit controlling device, in combination, a switch member movable about a fixed axis between open and closed circuit positions, an operating member manually shiftable between open and closed circuit positions, an over-center spring connecting said members and providing for snap movement of said switch member between open and closed positions 'by said operating member, and a. spring biased latch member normally held in a. given position and releasable upon overload to move said spring into a. position for eflectlng movement of said switch member to open circuit position and for also restoring said operating member to open circuit position, said latch member when released being resettable in normal position by movement of said operating member toward circuit closing position and said latch member when reset in normal position being movable out of such position free from interference by said operating member.

14. In a circuit controlling device, in combination, a movable circuit controlling member, a snap operating mechanism therefor including an operating member manually shiftable between open and closed circuit positions, said mechanism permitting movement of said circuit controlling member into open position free from interference by said operating member, an overload responsive device associated with said operating mechanism including a latched tripping part normally held in a given position and releasable upon given overload conditions to eifect movement of said switch member into open circuit position independently of said operating member, means for connecting said tripping part to said operating member to provide for resetting thereof upon movement of said operating part out of open circuit position, and means for disconnecting said tripping part from said operating member prior to full movement of said operating member into closed circuit position.

15. In a circuit controlling device, in combination, a switch member movable about a fixed axis between open and closed circuit positions, an operating member therefor manually shiftable between open and closed circuit positions, an overcenter spring connecting said members and providing for snap movement of said switch member between open and closed circuit positions by said operating member, an overload device ineluding a latched tripping part releasable upon overload to move said over-center spring into a position for moving said switch member into open position and for restoring said operating member to open circuit position, means for connecting said tripping part to said operating member to provide for resetting thereof upon movement of said operating member out of open position and means for disconnecting said latched tripping member from said operating member prior to full movement of said operating member into circuit closing position.

16. In a circuit interrupter not capable of being set to reclose automatically, means for opening and closing the circuit including a contact element movable about a pivot to open and closed positions, a pivoted operating member, a spring connected at one end to move said contact element about its pivot and connected at its other end to said operating member, said spring being movable by said operating member back and forth across the pivot of said contact element to thereby alternately bias said contact element to move to open and close the circuit with a snap action, and means responsive to a predetermined condition for applying a force to said spring at a point spaced from the end thereof connected to said operating member for moving said spring across the pivot of said contact element and thereby causing said spring to bias said contact element to move to and to. stay in open position even though the end of the spring connected to said operating member is held to prevent movement of said end of the spring.

1'7. In a circuit interrupter notcapable of being set to reclose automatically, a contact element movable about a fixed pivot to open and close the circuit, an operating member movable between an "on and an "of!" position about a fixed pivot adjacent the fixed pivot of said contact element, a spring connected at one end to actuate said contact element and connected at its other end to said operating member, said spring being movable across both of said pivots upon movement of said operating member and said spring changing the direction of the bias exerted on said contact element and on said operating member as it crosses their respective pivots, and means responsive to a predetermined condition for applying a force to said spring at a point spaced from the end thereof connected to said operating member for moving said spring across both of said pivots and at the same time increasing the stress thereof even though the end of the spring connected to said operating member is held in "on" position, said spring after being moved across said pivots by said means biasing said contact element to move to and to stay in open circuit position and biasing said operating member to move to "01! position, and said operating member at some time after operation of said means responsive to a predetermined condition being operable by a single movement from off" to "on position to reclose the circuit.

18. In a circuit interrupter not capable of being set to reclose automatically, means for opening and closing thecircuit including a contact element movable between two positions, an operating member movable between two positions, a spring connected at one end to move said contact element and connected at its other end to said operating member, said spring biasing said operating member to whichever of its positions it has been moved and in each case biasing said contact element to its position corresponding to the position of said operating member, and means responsive to a predetermined condition for applying a force to laterally move said spring at a point spaced from the end thereof connected to said operating member and said lateral motion of said spring causing it to change the direction of its bias applied to said contact element when it has been moved to a predetermined point and then acting to move said contact element to the other position and to remain in such other position even though the end of the spring connected to said operating member is held in its original position, and said spring when moved laterally by said current responsive means to a predetermined point also changing the direction of its bias applied to said operating member and tending to move it away from the position which it formerly occupied.

19. In electrical apparatus requiring manual operations for setting and resetting thereof, means for opening and for closing a circuit, said means being actuated to the open and to the closed position by a member having one point thereof movable to actuate said means to the open and to the closed position and being supported at a second point thereof, manually movable means exerting a force having a line of action normally lying to one side of said second point at which said actuating member is supported, and a second force exerting means responsive to a predetermined condition for automatically producing relative movement between said line of action and said'second point, whereby said line of action is moved to and caused to remain on the opposite side of said second point pending manual movements of said manually movable means, the iorce for eflecting relative movement of said line of action and said second point being supplied by said force exerting means responsive to a predetermined condition at a point spaced from the point at which said first means exerting a force is manually movable, said means for opening and for closing the circuit remaining in the closed position until there has been Sufllcient relative movement of said second point and said line oi action to cause said line oi! action to lie on the said opposite side or said point.

20. In electrical apparatus, means for opening and for closing a circuit, said means being actuated to the open and to the closed position -by a member having one point thereof movable to actuate said means to the open and to the closed position and being Supported at a second point thereof, means exerting a force having a line of action normally lying to one side of said second point at which said actuating member is supported, an operating member directly engaging said means exerting a force and movable between an open and a closed position for causing movement of said line of action back and forth across said second point to open and close the circuit at will under ordinary conditions, and a second force exerting means responsive to a predetermined condition and operable independently of the position in which said operating member may be held for automatically producing relative movement between said line of action and said second point, whereby said line of action is moved to the opposite side of said second point and caused to remain there pending movement and resetting of said operating member, the force for eiiecting relative movement of said line of action and said second point being supplied by said force exerting means responsive to a predetermined condition, said means for opening and for closing the circuit remaining in the closed position until there has been sufllcient relative movement of said second point and said line oi. action to cause said line of action to lie on the said opposite side of said point.

21. In electrical apparatus, means for opening and for closing a circuit, said means bein actuated to the open and to the closed position by a. member having one point thereof movable to actuate said means to the open and to the closed position and being supported at a second point thereof, means exerting a force having a line of action normally lying to one side of said second point at which said actuating member is supported, an operating member movable between an open and a closed position for causing movement of said line of action back and forth across said second point to open and close the circuit at will under ordinary conditions, and a second force exerting means operable only in response to a predetermined condition and independently oi the position in which said operating member may be held for beginning to exert a biasing force tending to produce relative movement between said line of action and said second point, whereby said line of action is moved to the opposite side of said second point and caused to remain there pending movement of said operating member from closed position toward open position and return toward closed position, the force for eil'ecting relative movement of said line of action and said second point being supplied by said force exerting means responsive to a predetermined condition, said means for opening and for closing the circuit remaining in the closed ment of said line of action in response to said predetermined condition causing said operating member to move to its open position if not held and the reclosing of said means for opening and closing the circuit then requiring no movement ofthe operating member other than a movement to closed position.

22. In a circuit interrupter not capable oi being set to reclose automatically, switching means actuable about a fixed pivot to cause opening and closing of the circuit, a pivoted operating member, a biasing spring connected at one end to actuate said switching means and at the other end in engagement with one point on said pivoted operating member, said operating member being movable about its pivot to'carry the line of action of the biasing spring across the fixed pivot oi the switching means to move the switching means to open and closed positions with a snap action, and current responsive means operable upon the occurrence of a predetermined condition to act on said biasing spring at a second point and move the line of action thereof across the fixed pivot of said switching means and to cause it to remain there, even though said operating member may be held in closed position, and cause said biasing spring to initiate movement of said switching means to open the circuit. a

23. In a circuit interrupter not capable of being set to reclose automatically, a contact member, mounted to move about a fixed pivot for opening and closing the circuit, a pivoted operating member, a tension spring connected at one end to actuate said contact member and at the other end to said pivoted operating member, a handle member for moving said operating member about its pivot and thereby move the direction of the bias of said tension spring across said fixed pivot of the contact member to normally move it to open and closed positions with a snap action, and current responsive means operable upon the occurrence of a predetermined abnormal condition to apply a force to said tension spring at a point spaced from the end of the spring connected to the pivoted operating member and move the direction of its bias on said contact member across the pivot of said contact member, said contact member remaining in closed position after movement of said current responsive means until said tension spring has moved across the pivot of said contact member to bias it to open position and then moving to and remaining in open position even though said handle member may be held in closed position.

24. In a circuit interrupter not capable of being set to reclose automatically, a contact'member mounted to move about a fixed pivot for opening and closingthe circuit, apivoted operating member, a tension spring connected at one action, and current responsive means operable upon the occurrence of a'predetermined abhor mal condition to apply a force to said tension spring and move the direction of its bias on said contact member across the pivot 01 said contact member, said contact member remaining in closed position after movement oi! said current responsive means until said tension spring has moved across the fixed pivot of the contact member to bias it to open position and then moving to and remaining in open position even though said handle member may be held in closed position, said handle member when released after being held in closed position being automatically moved to open position by said tension spring erating member being movable about its pivot to carry the line of action 0! said biasing spring across the fixed pivot of said switchina means, said biasing spring changing the direction oi the bias exerted on said switching means immediately upon each crossing of said iixed pivot to move said switching means to open and closed positions with a snap action, current responsive means operable upon the occurrence of a predetermined condition to move the direction oi the biasing force exerted on said switching means across the fixed pivot of the switching means to move it to open the circuit and to maintain the circuit open even though said operating member is held in closed position, said operating member when released after being held in closed position being moved by said biasing'spring to open position, and the circuit interrupter then being operable by movement or the operating member to closed position to move said switching means to close the circuit.

CLARENCE W. KUHN. 

